From blocking off the office heliport to plotting protests, workers at Venezuela's prosecutor's office are making plans to fight her expected removal by allies of President Nicolas Maduro, according to three sources.

Luisa Ortega, Venezuela's lead prosecutor and main challenger to Maduro from within the ruling socialist movement, has said she is expecting to be fired after alleging human rights abuses and erosion of democracy under the country's leftist president during three months of major anti-government
protests.

"We have to show unwavering support towards our state prosecutor, and if they do touch her, they will never be allowed to take over our institution," said an unofficial statement circulated by workers on Monday.

A heliport atop the prosecutor's main office in Caracas has been blocked off with furniture to avoid external interruptions, the sources said on Monday, requesting anonymity out of fear of reprisals.

The pro-government Supreme Court is considering a charge brought by a socialist lawmaker of "grave offense" against Ortega. Officials have also leveled a plethora of accusations against the 59-year-old lawyer, from "insanity" and encouraging "terrorists" to misusing a confiscated plane.

Amid an apparent bid to oust her, the top court named a deputy prosecutor, whom Ortega has rejected as illegitimate.

That court-appointed deputy prosecutor last week tried to enter the office hiding in the trunk of a car but was expelled by security personnel, a source at the prosecutor's office had told Reuters.

The internal fissure has emboldened anti-Maduro protesters, who have been staging near-daily demonstrations since April to demand early elections amid a devastating economic crisis that has millions struggling to eat properly. Almost 100 people have died in the unrest.

Protesters across the oil-rich South American nation were holding a 10-hour road blockade on Monday. Some demonstrators were sitting on garden chairs quietly reading a book or waving Venezuelan flags. Young hooded protesters also prepared Molotov cocktails, and were clashing with security forces in the capital.

"I'm fighting against these communists who don't know how to run the country and have stolen everything," said retiree Antonio Montero, who lives in the sprawling Petare slum, as he waved a Venezuelan flag in the middle of an empty Caracas street.

Many protesters feel vindicated after Venezuela's best-known jailed opposition leader Leopoldo Lopez was granted house arrest over the weekend.

The opposition is also seeking to ramp up pressure ahead of Maduro's planned vote on July 30 to elect members of a new, controversial legislative superbody with powers to rewrite the constitution.

Maduro has said the assembly is the only way to bring peace to Venezuela.

His opponents have said that it is a ruse designed to avoid free and fair elections that the Socialist Party would lose. The opposition is holding its own referendum on Sunday to let Venezuelans have their say.